We present an analysis of \sim 3.5 square degrees of submillimetre continuum and extinction data of the Perseus molecular cloud .
We identify 58 clumps in the submillimetre map and we identify 39 structures ( ‘ cores ’ ) and 11 associations of structures ( ‘ super cores ’ ) in the extinction map .
The cumulative mass distributions of the submillimetre clumps and extinction cores have steep slopes ( \alpha \sim 2 and 1.5 - 2 respectively ) , steeper than the Salpeter IMF ( \alpha = 1.35 ) , while the distribution of extinction super cores has a shallow slope ( \alpha \sim 1 ) .
Most of the submillimetre clumps are well fit by stable Bonnor-Ebert spheres with 10 K < T < 19 K and 5.5 < log _ { 10 } ( P _ { ext } /k ) < 6.0 .
The clumps are found only in the highest column density regions ( A _ { V } > 5 - 7 mag ) , although Bonnor-Ebert models suggest that we should have been able to detect them at lower column densities if they exist .
These observations provide a stronger case for an extinction threshold than that found in analysis of less sensitive observations of the Ophiuchus molecular cloud ( 33 ) .
The relationship between submillimetre clumps and their parent extinction core has been analyzed .
The submillimetre clumps tend to lie offset from the larger extinction peaks , suggesting the clumps formed via an external triggering event , consistent with previous observations .